Turtle Lake lies in a NE-SW direction and has a
maximum length of slightly over 20 km and a maximum width of 5-6 km. The lake
is relatively shallow with an average depth of 5.6 m and a maximum depth of 14.3
m. The deepest part of the lake is in the centre of the lake west of Sunset
View cottage subdivision. Areas less than 5 m in depth account for 52% of the
total water surface. The northern half of the lake, including Mikinak Lake at
the very northern end, is very shallow (mostly less than 0.6 m).

Growth of emergent vegetation covers about 20% of the
littoral zone (shallow water area near shore) in the southern half of the lake.
Bulrush is the predominant species, followed by cattail, sedge and phragmites.
Emergent macrophytes cover a large portion of the northern half of the lake.

Fish species of most interest to lake users (i.e. northern
pike, walleye, yellow perch and lake whitefish) all use the littoral zone for
spawning and rearing purposes. Northern pike and yellow perch generally prefer
vegetated areas for spawning and rearing. The many weed beds in the shallow
northern half of the lake provide a diverse habitat not only for these two, but
also for other fish species.

Because walleye are not overly abundant in Turtle Lake, it
appears that habitat is marginal for walleye. Lack of suitable spawning streams
rather than nursery grounds is probably the main reason. Areas within the lake
that can be considered as potential walleye spawning habitat are those windswept
areas with bottom substrate ranging from sand and gravel to gravel and rocks of
various sizes. The increase in abundance of walleye in recent years can likely
be attributed mostly to the stocking program, but there is some indication that
walleye have adapted to spawning in the lake as well. About 80% of the
shoreline in the southern half of the lake consists of some combination of
rocks, sand and gravel.

Overall, Turtle Lake has a good mix of habitat for a
variety of fish species.

Fisheries Studies

An in-depth fisheries survey was conducted on
Turtle Lake in 1964-65, and the findings are reported in the Fisheries Branch
Technical Report “Report on Biology of the Turtle Lake Fishery” (Dr. W.W.
Sawchyn, 1967).

Ten species of fish were recorded from Turtle Lake
during the 1964-65 fisheries survey.

Large SpeciesForage (smaller)Species

Northern
pike Spottail
shiner

Walleye
Iowa darter

Lake Whitefish
Brook stickleback

Yellow perch

Common white sucker

Cisco

Burbot

Fish Stocking

The fish stocking program on Turtle Lake dates back
to 1927, and has been ongoing with some regularity over the past 80 years. Two
species have been the focus of the stocking program in an effort to bolster
their populations – walleye and lake whitefish.

Walleye

From 1932 – 1962, over 14 million walleye fry (newly
hatched) were stocked in the lake. The fisheries survey of 1964-65 indicated
poor stocking success, so the stocking program was terminated. But due to high
angler demand for walleye in the late 1960s, the walleye stocking program was
re-introduced. From 1969 – 2004, another 22 million walleye fry as well as
461,300 walleye fingerlings (about 5 cm long) were stocked. Currently, Turtle
Lake is stocked with approximately 500,000 walleye fry each spring.

Whitefish

Whitefish stocking started in 1927 and was discontinued in
1984. During this period, tens of millions of whitefish fry were stocked. The
most extensive stocking occurred from 1969 – 1980 when 13 million fry were
stocked in the lake.

Sport Fishery

Turtle Lake is a heavily utilized recreational
lake, with over 1500 cottages. Northern pike is the mainstay of the
recreational fishery, with many large fish taken annually by anglers. The
abundance of natural pike habitat, as well as the abundance of forage fish,
allows the pike population to flourish. The pike population has always been
maintained through natural reproduction in the lake.

Walleye is the choice of many anglers, but the number of
angling size fish has been low through most of the past 40-50 years, despite the
large numbers of walleye stocked in an effort to increase the population. There
are recent indications that the walleye stocking program is beginning to show
signs of success. The latest trap net (live capture and release) survey by
Fisheries Branch in 2003 caught a significant number of walleye, represented by
several age classes from 2 – 8 years of age. Walleye represented by the 4 – 8
year age classes represent the ideal size fish for angling, and there were lots
of these fish in the trap nets. Anglers also catch burbot and lake whitefish
during the ice fishing season.

Perch, which is another favorite sport fish species in
Saskatchewan, is fairly abundant in Turtle Lake but does not grow large enough
in the lake to be of angling size. Because of its small size, it serves as a
forage fish for pike and walleye.

Commercial Fishery

A commercial fishery for whitefish was in existence
on Turtle Lake since the year 1900 (Dominion Alberta and Saskatchewan
Commission Report 1910-1911). There were a few declines in the fishery
during the first half of the 20th century with some population
declines lasting up to five years.

Turtle Lake had a commercial quota for whitefish of 75,000
lb annually, and production averaged 60,000 lb per year until 1963. Local
residents from around the lake participated in the annual winter fishery; a fish
packing plant was located at Moonlight Bay on the west side of the lake. The
whitefish population collapsed in 1963 and production averaged only 5200 lb/year
until 1977, after which the lake was no longer fished commercially. The reason
for the collapse is unknown, but a combination of fishing pressure and
intermittent spawning success may have been responsible. There has been some
indication the whitefish spawn in the shallow north end of the lake and in
Mikinak Lake, both of which are subject to winterkill (therefore the eggs, which
are laid in late fall, would not survive through the winter). The extensive
stocking program was not successful at revitalizing the population.

The Turtle Lake Monster

Much has been reported and written over the years
about the Turtle Lake “monster” (although nothing has been reported in recent
years). Over the years, people fishing in the open water have reported
sightings of a big “thing” swimming near their boat. Could it have been a lake
sturgeon?

Lake sturgeon inhabit the Saskatchewan River system, and
the outflow from Turtle Lake flows via the Turtle River directly into the North
Saskatchewan River. It is not inconceivable during some years of very high
outflow that sturgeon could have found their way from the North Saskatchewan up
the Turtle River and into Turtle Lake. Sturgeon have a very long life span, so
the few that may have entered the lake could have stayed there for many
decades. And of course, the longer they lived in the lake, the larger they
grew. Sturgeon are bottom feeding fish, so they wouldn’t often be sighted near
the surface.

The presence of a few slake sturgeon is the most plausible
explanation for the numerous reported sightings of a “monster” swimming in the
waters of Turtle Lake. Having said this, sturgeon have never been caught in any
test netting surveys, nor in any commercial fishing nets, so there is no
conclusive evidence of their presence in the lake. However, there are
similarities between Turtle Lake and Candle Lake in regards to their connection
to the Saskatchewan River system; in the case of Candle Lake, a few large lake
sturgeon have actually been caught which verifies they were able to find their
way upstream and take up residence in the lake. But for Turtle Lake we’ll
likely never know for sure!

Walleye fish population in Turtle Lake healthy & growing

Gord Sedgewick, Biologist for Saskatchewan
Environment provided attendees at the Turtle Lake Watershed Inc. 2010 Annual
General Meeting with an interesting and current presentation about the
status of the fishery in Turtle Lake. After setting 11 gillnets and 3
trap nets in the lake in early July, Sedgewick reported that his team had
caught 1,473 fish of which 53% were walleye and 9% were Northern Pike.
"Turtle Lake can now be called a predominantly walleye fishery and the
walleye are of all ages and sizes with many ranging from 5 to 8 pounds",
reported Sedgewick. He went on to report that "they are very healthy with
lots of fat on them." When asked if he knew if walleye were reproducing
naturally in Turtle Lake, Sedgewick said that he had not completed the
research to determine that.

Walleye have been stocked annually in Turtle Lake, since
the early 90's and it appears those efforts are paying off. Sask
Environment places 500,000 walleye fry in Turtle Lake every spring, however none
were stocked this year. Going forward, Sask Environment plans on stocking
1 million walleye fry in Turtle Lake every other year.